Many types of airbag systems have been proposed that restrain the body parts of a vehicle occupant during a collision. These systems typically include an airbag that is housed within a housing and an inflator that selectively provides fluid to inflate the airbag. During a collision, the occupant's inertia tends to cause the occupant's body to move. However, the collision triggers the inflator to inflate the airbag, and the occupant's body can be decelerated, cushioned, and restrained from excess movement by the airbag.
Some airbag systems are adapted to restrain the knees and lower legs of the occupant (i.e., “knee airbags”). These knee airbags can be mounted in various positions relative to the instrument panel and/or relative to the occupant's seat. Thus, during a collision, the airbag can inflate toward the occupant's knees and lower legs to restrain movement of the knees and/or lower legs.